Rav Judah said in the name of Samuel: peace-offerings slaughtered before the doors of the Sanctuary are opened are invalid, as it is written, "and he shall slaughter it at the entrance of the tent of meeting" - at a time when it is open, and not at a time when it is shut. But this is written concerning the Tabernacle! We find the Temple called "Tabernacle," as it is written, "And I will set My Tabernacle among you" (Leviticus 26:11), and the Tabernacle called "Sanctuary," as it is written, "And let them make Me a sanctuary, and I will dwell among them." From where do we know about ritual impurity in the Temple court? Rabbi Eliezer said: one verse says (Numbers 19:13), "he has defiled the Tabernacle of the LORD," and another verse says, "he has defiled the Sanctuary of the LORD." If it is not needed for the matter of impurity outside [in the open], apply it to the matter of impurity within. But are the verses superfluous? Surely each is needed! As it was taught, Rabbi Eliezer says: if "Sanctuary" is stated, why is "Tabernacle" stated, and if "Tabernacle" is stated, why is "Sanctuary" stated? Had "Tabernacle" been stated and not "Sanctuary," I would have said that for the Tabernacle he is liable, since it was anointed with the anointing oil, but for the Sanctuary he would not be liable. And had "Sanctuary" been stated and not "Tabernacle," I would have said that for the Sanctuary he is liable, since its holiness is an eternal holiness, but for the Tabernacle he would not be liable. Therefore "Sanctuary" is stated and "Tabernacle" is stated. Rabbi Eliezer found this difficult: since the Tabernacle is called "Sanctuary" and the Sanctuary is called "Tabernacle," why are two verses needed? If not needed for the matter of impurity outside, apply it to impurity within. Granted that the Temple is called "Tabernacle," as it is written, "And I will set My Tabernacle among you" (Leviticus 26:11), but from where do we know the Tabernacle is called "Sanctuary"? As it is written, "And let them make Me a sanctuary, and I will dwell among them," and it is written, "according to all that I show you, the pattern of the Tabernacle."
Why Scripture Names the Shrine Both Tabernacle and Sanctuary
Yalkut Shimoni on Torah 366:1
אֲמַר רַב יְהוּדָה אֲמַר שְׁמוּאֵל, שְׁלָמִים שֶׁשְּׁחָטָן קֹדֶם פְּתִיחַת דַּלְתוֹת הַהֵיכָל פְּסוּלִין, דִּכְתִיב "וּשְׁחָטוֹ פֶּתַח אֹהֶל מוֹעֵד", בִּזְמַן שֶׁפָּתוּחַ וְלֹא בִּזְמַן שֶׁנָּעוּל. הַאי בַּמִּשְׁכָּן כְּתִיב. אַשְׁכְּחָן מִקְדָּשׁ דְּאִקְרֵי מִשְׁכָּן דִּכְתִיב וְנָתַתִּי מִשְׁכָּנִי בְּתוֹכֲכֶם, וּמִשְׁכָּן דְּאִקְרֵי מִקְדָּשׁ דִּכְתִיב וְעָשׂוּ לִי מִקְדָּשׁ וְשָׁכַנְתִּי בְּתוֹכָם. טֻמְאָה בָּעֲזָרָה מִנָּא לָן. אָמַר רַבִּי אֱלִיעֶזֶר, כָּתוּב אֶחָד אוֹמֵר (במדבר יט, יג) "אֶת מִשְׁכַּן ה' טִמֵּא" וְכָתוּב אֶחָד אוֹמֵר "אֶת מִקְדָּשׁ ה' טִמֵּא", אִם אֵינוֹ עִנְיָן לְטֻמְאָה שֶׁבַּחוּץ תְּנֵהוּ עִנְיָן לְטֻמְאָה שֶׁבִּפְנִים. וּקְרָאֵי מִי מְיַיתְּרֵי, הָא מַצְרָךְ צְרִיכֵי, דְּתַנְיָא, רַבִּי אֱלִיעֶזֶר אוֹמֵר, אִם נֶאֱמַר מִקְדָּשׁ לָמָּה נֶאֱמַר מִשְׁכָּן וְאִם נֶאֱמַר מִשְׁכָּן לָמָּה נֶאֱמַר מִקְדָּשׁ, אִלּוּ נֶאֱמַר מִשְׁכָּן וְלֹא נֶאֱמַר מִקְדָּשׁ הָיִיתִי אוֹמֵר עַל מִשְׁכָּן יְהֵא חַיָּב שֶׁהֲרֵי מָשׁוּחַ בְּשֶׁמֶן הַמִּשְׁחָה וְעַל מִקְדָּשׁ לֹא יְהֵא חַיָּב, וְאִם נֶאֱמַר מִקְדָּשׁ וְלֹא נֶאֱמַר מִשְׁכָּן הָיִיתִי אוֹמֵר עַל מִקְדָּשׁ יְהֵא חַיָּב שֶׁהֲרֵי קְדֻשָּׁתוֹ קְדֻשַּׁת עוֹלָם וְעַל מִשְׁכָּן לֹא יְהֵא חַיָּב, לְכָךְ נֶאֱמַר מִקְדָּשׁ וּלְכָךְ נֶאֱמַר מִשְׁכָּן. רַבִּי אֱלִיעֶזֶר הָכִי קַשְׁיָא לֵיהּ, מִכְדֵי מִשְׁכָּן אִקְרִי מִקְדָּשׁ וּמִקְדָּשׁ אִקְרֵי מִשְׁכָּן, תְּרֵי קְרָאֵי לָמָּה לִי, אִם אֵינוֹ עִנְיָן לְטֻמְאָה שֶׁבַּחוּץ תְּנֵהוּ עִנְיָן לְטֻמְאָה שֶׁבִּפְנִים, בִּשְׁלָמָא מִקְדָּשׁ דְּאִקְרֵי מִשְׁכָּן דִּכְתִיב (ויקרא כו, א) "וְנָתַתִּי מִשְׁכָּנִי בְּתוֹכֲכֶם", אֶלָּא מִשְׁכָּן דְּאִקְרֵי מִקְדָּשׁ מִנָּא לָן, דִּכְתִיב וְעָשׂוּ לִי מִקְדָּשׁ וְשָׁכַנְתִּי בְּתוֹכָם, וּכְתִיב כְּכֹל אֲשֶׁר אֲנִי מַרְאֶה אוֹתְךָ אֵת תַּבְנִית הַמִּשְׁכָּן.